Increase In Energy Values Research Articles

Renewable-battery hybrid power plants in congested electricity markets: Implications for plant configuration

Examining coupled renewable-battery power plants (“hybrids”) in congested areas provides insights into a future of increased wind and solar penetration. Our study focuses on two types of congested regions, Variable Renewable Energy (VRE)-rich Areas and Load Centers, and explores likely plant configuration choices for developers and transmission network planners. This paper examines how hybrid value, comprising energy and capacity value, varies by plant configuration and congested region type considering factors such as storage duration, battery degradation, and ability to charge from the grid. We select plant locations from across the seven main U.S. independent system operators (ISOs). Hybrid value for each configuration is computed based on profit-maximizing plant operation given perfect foresight, according to observed wholesale power market real time prices from 2018 to 2021. In VRE-rich Areas, the median increase in energy value from extending storage duration from one to 4 h is 29.4 % for solar and 26.8 % for wind, assuming low battery degradation costs and storage sized to 100 % of the plant's nameplate generation capacity. Increasing storage duration beyond 4 h does not substantially increase its value from energy markets, even in VRE-rich Areas. We find that solar hybrids reach a 90 % capacity credit with 4 h of storage, while wind hybrids require 8 h of storage, based on the capacity factor of each hybrid during the top 100 net load hours.

Novel biscuits using whey protein and Ocimum gratissimum to mitigate protein burden: Quality parameters, in vitro protein digestibility, SWOT analysis and implication on public health

Biscuits are the most popular ready-to-eat snack consumed worldwide. It can serve as convenient carrier of nutritionally rich ingredients, targeting large variety of populations. In the present study, antioxidative protein-enriched functional biscuits were prepared by adding Ocimum gratissimum leaves and by partially replacing whole wheat flour with whey protein concentrate (WPC) (10 % to 70 % substitution on w/w basis). Effects of such incorporation on the product’s physico-chemical and organoleptic properties were evaluated and compared against a control biscuit that was devoid of WPC and Ocimum sp. Increase in biscuits’ volume and thickness, and decrease in their bulk density and spread ratio were noted with the escalating amount of WPC. Rise in WPC concentration improved the nutritional parameters of biscuits, namely crude protein (8.01 % to 29.84 %; ≈80.43 % enhancement), total ash (2.46 % to 3.36 %), fat (21.03 % to 23.53 %) and antioxidant activity (39.67 % to 53.02 % radical scavenging property). A net increase in energy value of 11.12 % and in vitro protein digestibility of 12.91 % was seen in the sample having the highest level of substitution. Though all the protein-enriched biscuits were found to be sensory satisfactory, 50 % replacement of wheat flour by WPC received the optimum liking and those with the higher level of substitution are envisioned to meet the daily requirement of protein suggested for children and adults. Using SWOT analysis, few threats and weakness of the product were identified, which needs to be tackled in future product improvement.

English

Wild fruits contribute significantly to food security, thus becoming an important global discussion. This study evaluated the physicochemical and nutritional properties of Syzygium cumini (L.) Skeels fruits from two microclimates in Kenya as essential contributors to the human diet. Analysis was done using standard methodologies including the use of inductively coupled plasma - optical emission spectrometer for elemental analysis and high-pressure liquid chromatography for the determination of Vitamin C. The T-test showed significant differences in the fruit breadth, pH, total ash, sodium, calcium, manganese, copper, and zinc. The Pearson correlation matrix showed a small positive association between total soluble solids and titratable acidity with altitude, a medium positive correlation with rainfall, and a strong positive correlation between sunshine and skin colour intensity. Larger fruits contained substantial amounts of protein and crude fiber with a significant increase in energy values in fruits with high crude fat and carbohydrates, all correlating positively with the microclimate conditions; altitude, and rainfall. This study exemplifies the potential of Syzygium cumini as an alternative feed supplement to strengthen food security. It provides information on the variation of the physicochemical and nutritional composition of the fruits with climatic conditions, for the industries to employ the best strategies in obtaining marketable products. Key words: Food security, fruit quality, microclimate, nutritional, physicochemical, Syzygium cumini

Analysis of indicators of quality and safety of meat of broiler chickens under the conditions of complex use of symbiotic and biocidal drugs during the entire breeding cycle

The production of ecologically clean poultry meat with high biological value to meet the needs of public demand is the primary goal of the poultry industry. Poultry meat is a good product for a healthy human diet due to its nutritional, dietary, and sensory properties, economic availability, and quick cooking. At the same time, using the latest, effective symbiotic and biocidal drugs to increase the productivity of poultry requires more in-depth research and evaluation of their impact on the final product. Based on the analysis of the results obtained by us, it has been proven that the use of the complex of symbiotic drugs “Biomagn” and “Biozapin” and in combination with the biocidal agents “Diolaid” and “Biolaid” to broiler chickens of the Cobb 500 cross throughout the entire breeding cycle allows obtaining high-quality and safe poultry products (chicken meat), with improved quality indicators and higher biological value. An increase in the protein content in the muscles of experimental groups of birds and a decrease in moisture in them was established, which is a consequence of an increase in dry matter content in this tissue. As a result, in the muscles of broiler chickens of the II research group, an increase in energy value was recorded to a greater extent and markedly, along with an increase in the content of essential bioelements (Calcium, Ferrum, Copper, Cobalt, and Selenium (Р ≤ 0.05)) and the content of vitamins A and B1, which indicates a higher biological (nutritional) value of poultry meat compared to such indicators in poultry I of the experimental and control groups. When determining the safety indicators of the chicken meat of the research groups, it was established that there were no residual amounts of veterinary drugs, pesticides, and aflatoxin B1, and the regulated indicators of toxic elements did not exceed the PAI specified in the regulatory documents. Therefore, the proposed complex of drugs in the scheme of the growing cycle of broiler chickens does not hurt the quality and safety of the obtained products (chicken meat). On the contrary, according to sensory and organoleptic studies, higher organoleptic qualities of the muscle samples of chickens of the I and II experimental groups were proven under the conditions of the use of a complex of symbiotic and biocidal drugs: the values of the highest overall score for tasting the meat broth are higher (Р ≤ 0.05) compared with the indicator in the control group.

Torrefaction and Densification of Wood Sawdust for Bioenergy Applications

In this study, wood sawdust as waste residue from wood processing mills was pretreated using torrefaction to improve fuel properties and densified to facilitate transportation. Sawdust was torrefied in a fixed bed reactor using inside temperatures (IT) of 230, 260 and 290 °C for 15, 30 and 45 min, residence time. Due to the low calorific value of the treatments, the outside temperature (OT) of the fixed bed reactor was used instead for a fixed duration of 45 min, which resulted in an increase in energy value by 40% for the most severe conditions. The mechanical strength of the pellets was enhanced by adding 20% binder (steam-treated spruce sawdust) to biochar, which improved the pellet tensile strength by 50%. Liquid by-products from the torrefaction process contained furfural and acetic acid, which can be separated for commercial uses. Thermochemical analysis showed better fuel properties of OT torrefied samples such as high fixed carbon (52%), low volatiles (41%) and lower oxygen contents (27%) compared to IT torrefied samples (18, 77 and 43%, respectively). Low moisture uptake of torrefied pellets compared to raw pellets, along with other attributes such as renewability, make them competent substitutes to fossil-based energy carriers such as coal.

Valuing Enhanced Hydrologic Data and Forecasting for Informing Hydropower Operations

Climate change is rapidly modifying historic river flows and snowpack conditions in the Sierra Nevada in California and other seasonally snow-covered mountains. Statistical forecasting methods based on regressing summer flow against spring snow water equivalent, precipitation, and antecedent runoff are thus becoming increasingly inadequate for water-resources decision making, which can lead to missed opportunities in maximizing beneficial uses, including the value of hydropower resources. An enhanced forecasting method using a process-based model and spatially distributed wireless sensor data offers more accurate runoff forecasts. In this paper, we assessed the forecasting accuracy of these two forecasting methods by applying them to two tributaries within the North Fork Feather River basin in California. The result shows the enhanced forecasting method having better accuracy than the statistical model. In addition, a hydropower simulation showed a considerable increase in energy value with the enhanced forecasting informing reservoir operations. The investment analysis on applying this method shows an average internal rate of return of 31% across all scenarios, making this forecasting method an attractive way to better inform water-related decisions for hydropower generation in the context of climate change.

Effect of Ni concentration on optical properties of rocksalt CdS system (A DFT + U study)

Present study is a computational approach focused on optical properties of Ni-doped rocksalt CdS system under PBE-GGA and GGA + U approximations. Investigation of optical properties of CdS:Ni system by fixing supercell size and increasing dopant concentration is a focus of study. Cd atoms are substituted by Ni atoms and optical properties show significant change for higher Ni concentration. Redshift in optical absorption is observed as dopant concentration is increased. Interaction of Ni and S atoms and localization of d-states are inspected near the conduction band minima or Fermi surface. GGA + U absorption plots show slight variation with increase in energy values. Ni-doping in CdS host lattice enhances its opto-electronic properties which extend its applications in optical sensors, optical and similar devices.

Effect of tigernut (Cyperus esculentus) flour addition on the quality of wheat‐based cake

SummaryThe effect of substituting tigernut flour for wheat flour on the proximate, mineral and pasting properties of the resultant blends and cake quality were studied. The proximate composition of flour blends increased with increasing level of tigernut. Protein increased from 22.30 to 26.93% and fat from 4.17 to 7.21% resulting in an increase in energy value from 342.09 to 390.93 kcal. The pasting properties of the flour blends were affected significantly (P ≤ 0.05) by tigernut substitution. Pasting peak time and temperature decreased with increasing level of tigernut. Mineral elements such as iron and calcium increased from 3.13 to 4.19 and 54.01 to 56.41 (mg 100 g−1) respectively, with tigernut substitution. The weight and volume of cakes increased with tigernut level while batter density and volume index decreased. Acceptable cakes can be made with up to 30% tigernut flour substitution. Such composite cakes may help in reducing protein energy and micronutrient deficiencies.

Effects of wheat variety and specific weight on dietary apparent metabolisable energy concentration and performance of broiler chicks

1. This study used 4 wheat cultivars (Brigadier, Chaucer, Consort, Reaper) from three locations (Crossnacreevy, C; Downpatrick, D; Limavady, L), which had given rise to differences in wheat specific weight (SW), to examine the relationships between apparent metabolisable energy (AME) concentration, broiler performance and wheat SW. 2. The diets contained (g/kg): wheat 744, casein 142, blended vegetable fat 50, dicalcium phosphate 22, potassium bicarbonate 10.8, sodium bicarbonate 7.5, arginine 5, methionine 2, binder 8, trace minerals/vitamins 7.2, titanium dioxide 1.5. The diets were heat-treated (80°C for 2 min) prior to pelleting (3 mm die). 3. SW ranged from 63 to 77 kg/hectolitre (hl), averaging 66, 69 and 76 kg/hl at D, C and L, respectively. In vitro viscosity of the wheat samples ranged from 5.2 to 17.5 cps and thousand grain weight (TGW) from 33.4 to 47.3 g. Mean TGW was similar at C and D (38.7, 37.0 g) but higher at L (43.1 g). In vitro viscosity was similar at C and L (11.2, 10.2 cps) but somewhat higher at D (14.4 cps). Crude protein (6.25 N) ranged from 116 to 147 g/kg and tended to be higher at D. Starch, which ranged from 612 to 656 g/kg, was least at D (617 g/kg) and greatest at L (641 g/kg). 4. Crude protein, crude fibre and total non-starch polysaccharide (NSP) were negatively correlated with SW, the R 2 being respectively 0.38 (P <0.05), 0.16 (NS) and 0.45 (P <0.05). TGW and starch concentration were positively correlated with SW (R 2=0.70, 0.44, respectively). There was a weak (NS) negative relationship (R 2=0.19) between in vitro viscosity and SW. For both TGW and in vitro viscosity, correlations improved when variety was taken into account (R 2=0.95, 0.92, respectively). 5. There were no significant effects of variety on dry matter (DM) intake or live weight gain (LWG). Gain: food was significantly higher (P <0.05) for Consort than for the other three varieties and the metabolisable energy ratio (ME:GE) just failed to attain significance (P =0.062). Calculated wheat AME (MJ/kg DM) was significantly (P <0.05) higher for Consort than for the other three wheats. There was a good correlation (R 2=0.49) for the total data set between gain:food and ME:GE. In vivo viscosity varied from 13.6 to 28.6 cps for individual treatments and was significantly affected by variety (P <0.001). 6. Although there were no significant differences in DM intake or LWG due to site the values for L (SW 76) were 6 and 5% lower, respectively, than for D (SW 66). Gain:food was lower (P <0.05) for C (SW 69) than for D. ME:GE, wheat AME and ME:gain were not significantly different between sites. 7. There was a weak (R 2=0.18) positive relationship between ME:GE and SW corresponding to a 2.5% increase in energy value for a 10 kg/hl increase in SW and no relationship between gain:food and SW. When variety was taken into the regression the slope was similar but R 2 increased to 0.82. 8. ME:GE and wheat AME concentration were negatively correlated with wheat in vitro viscosity (R 2=0.64, 0.55, respectively). 9. It was concluded that in vitro viscosity appears to provide a better basis than SW for prediction of the nutritive value of wheats of unknown variety. If the variety is known then SW could be used to predict energy value. However, the effect of quite a large change in SW (10 kg/hl) was relatively